No Spark on My Tohatsu M35B....Help

Bushwacker12

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Jun 17, 2011
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So I just brought my boat back from the Lake last week where it has been sitting for a year or so and I was hoping that a good carb clean would get her back going but that was wishful thinking. The motor ran when I parked it but now I do not have spark. So I started going thru it last night.

I was hoping it was an easy kill swithch problem but that's not the case. I have an old manual that goes from the M2.5B to the 40C models but it does not include the M35B. So I was using the test procedures for the 30-40 motors to see if I could find something obvious. I am using a Fluke digital multi-meter to do the ohms checks and found no ohms on the red wire (Exciter Coil?). I got 28-32 ohm reading on the blue wire (trigger coil) From some of the posts that I have read I'm guesssing I need to find a Digital meter with a 3v or less battery so I don't blow something, right? Did not do and tests on the CDI cause it looks fine and I would not think it would go bad from sitting?

I have read a lot of posts out on the net and I'm not getting a warm fuzzy about the chances of getting it fixed. From what I've seen from the "Tohatsu Guru", there may not be parts available for this motor and that will really bum me out cause I really like this motor and can't afford to replace it right now.

One thoutht that I had was to pull the flywheel off and see if there is a rust built up on the magneto. I've seen this problem on other motors and if I clean and sand the contact points that has fixes the problem. Problem was I did not have the special Tohatsu flywheel puller that they recommend. I did not want to try my old school trick of smacking the side with a hammer to see if it would pop off, anyone every try that approach and get it to work?

Anyone have some thoughts on this? Has anyone found a place to get parts (new or used) for this motor in case I do need an electrical component?

Thanks.
 

TOHATSU GURU

Admiral
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Jul 22, 2004
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Re: No Spark on My Tohatsu M35B....Help

Parts are not available...It's a dumpster anchor....Run away!!!
 

Bushwacker12

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Re: No Spark on My Tohatsu M35B....Help

Ouch, that sucks....guess I'll drag it out and make a reef of the whole thing, huh.
 

TOHATSU GURU

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Re: No Spark on My Tohatsu M35B....Help

I would...Not really:) But, I wouldn't put ANY money into it at all. Literally anything that you fix today will be pointless when something else breaks tomorrow. It's thirty years old so it has lasted way longer than the Japs ever thought it would be in service. Put it up on ebay and some other guy will buy it from you for a parts engine. Or, start looking for a 35 B parts motor yourself.
 

pvanv

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Re: No Spark on My Tohatsu M35B....Help

What Elvin said, plus:

I am using a Fluke digital multi-meter to do the ohms checks and found no ohms on the red wire (Exciter Coil?). I got 28-32 ohm reading on the blue wire (trigger coil) From some of the posts that I have read I'm guesssing I need to find a Digital meter with a 3v or less battery so I don't blow something, right? Did not do and tests on the CDI cause it looks fine and I would not think it would go bad from sitting?

One thoutht that I had was to pull the flywheel off and see if there is a rust built up on the magneto. I've seen this problem on other motors and if I clean and sand the contact points that has fixes the problem. Problem was I did not have the special Tohatsu flywheel puller that they recommend. I did not want to try my old school trick of smacking the side with a hammer to see if it would pop off, anyone every try that approach and get it to work?

You cannot use digital ohm meters on these. It must be a good analog meter, and must be powered by 3v or less. When you say "no ohms" for the exciter coil, do you mean Zero ohms, or Infinite resistance? Infinity is a cracked wire in the coil. Zero is a dead short. Either way, the coil is toast. You clearly do not understand the ignition system on this motor. Mags with exciters and triggers don't use contact points, so there is nothing to clean. A good harmonic balancer puller will work on that flywheel, but there is nothing to do in there unless you have a replacement exciter, which is NLA. No parts are available for this motor, so you either need to replace it, or buy a parts motor.
 

Bushwacker12

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Re: No Spark on My Tohatsu M35B....Help

Yeah, have been doinig the E-bay and Craigslist thing without any luck so far. One can only hope but it's not sounding too optomistic.

Found some stuff but without knowing the P/N of the coils and not having a book to referance it's going to be hard to figure out what I am looking for. Do either of you happen to know where I can find the part number or know it by chance? If this motor is shot I'm not going to put mony out for a manual that's for sure.

Guru, being your here in the Tampa area you know of any shops around the area that deal with used motors and parts that I could call or go to and see if I can get lucky?

Paul, you are right I am appling old school small engine repair to the problem. I just did not want to accept the fact that the coil could go bad from sitting. When I said I get no reading I mean that the meter did not move (showed OL) to ground. I also am just testing the readings to the plug/connector, I am not pulling the cord and that may be wrong too. Stilll looking for a analog meter, though I had one around, but I'll find one just to do the test correctly and get a better understanding.

Tried my harmonic puller on it last night and the thing would not budge so I gave up and was going to try again today. As I can't use it I don't mind pulling it apart and looking at it just for S*its and grins.

Thanks for all the input guys, just wish it was better news.
 

pvanv

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Re: No Spark on My Tohatsu M35B....Help

The electrical tests are done with the connectors disconnected. A reading that just shows OL on a digital meter is infinite ohms. In other words, no connection. A cracked wire or winding could cause that, and if testing with a super-high-impedance digital meter, some oxidation on a connector could also give a result like that.

When you have the puller on the flywheel and tensioned, you can (gently at first) smack the end of the puller bolt with a hammer, setting up a vibration. That may pop the taper free.

But, again, except to satisfy curiosity, I wouldn't spend any more time on it. Sad news, yes, but that's the way it is.
 

Bushwacker12

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Re: No Spark on My Tohatsu M35B....Help

Thanks Paul, I got it off yesterday basicly doing that same trick. As you called everything looked brand new up under there. I went and bought a digital meter to run the tests and looks like the Exciter is shot. Funny thing is a couple times on testing it I did get a small reading on it then it went away. I can see where you and Guru are saying not to waste time and money on this. If I find a used one someone will want to sell me the whole plate(stator assy?) because the plug is attached to all 3 coils. So can't imaging that not being cheep and if I did find a coil I'd have to sodder it on and I'm guessing that would not be a recommended practice. So I'm going to check my local Tohatsu repair shop to see if maybe they have one back in a corner somewhere and if not I guess I'm moving on....it's sad it's been a good motor for me for about 12 years now.

Want to keep a 25 to 35 on the boat it pushes it good but there hard to find on Craigs list. I came accross a 30hp Tohatsu and sent the guy an e-mail about it and what might be wrong and waiting on a reply. Are there any of the 30's that I should stay clear of ot things I should look for if I hear from the guy?

Thanks,
Tim
 

Bushwacker12

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Jun 17, 2011
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Re: No Spark on My Tohatsu M35B....Help

Found a 40C model but by the looks of the pictures it's a little rough. Problem is it's not a tiller model. So a couple questions:
- Would there be interchangable parts with my 35B, lower unit, heads, carb, ect...?
- Could I install the tiller handle from my 35?
- Guy claims it's an '87 M40C, are there going to be electronic parts available for it?
 

TOHATSU GURU

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Jul 22, 2004
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Re: No Spark on My Tohatsu M35B....Help

Some of the stuff, like the cast housings, will fit. But the rest of the crap would not be correct. I think the tiller handle is the same and the CDI is still available, but you are talking about going from an engine that is older than dirt to one that is just older than most people in college...Your jumping from the fire into the frying pan. Yeah, it's an improvement, but your still going to get fried.
 

Bushwacker12

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Jun 17, 2011
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Re: No Spark on My Tohatsu M35B....Help

Ok thanks, that's kind of what I though, something that old is just not worth it. Just not finding a decent size motor out there that isn't older than dirt or cost half a fortune. The Monark that the motor is on is just as old and it too has some issues so my school of thought is not to dump a bunch of money into this set up. Probably try to sell the whole thing for a few bucks and get something else a little bigger and better.

I have one last try on this coil which may be a shot in the dark but, I found a place on-line that rebuilds and returns the coils for Tohatsu models. The name of the place is CDI Electronics. I spoke to a tech yesterday and he said they did do some but without a part number he was not sure if mine was rebuildable. I looked last night and there is no P/N on it so he told me to sent it in for evaluation they would be able to tell me if they could so I think I'll give it a try. When you check there web site they show pictures and model numbers of these coils and they all look the same. I would have thought there would be a physical differance in the coils but I guess their internal windings change or something? If they can do it it'll cost less than 100 bucks so I'll gamble on this and let ya know.

Thanks again for all the advise.
 

Bushwacker12

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Jun 17, 2011
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Re: No Spark on My Tohatsu M35B....Help

Just wanted to update you on the progress. Sent the exciter coil to CDI and they repaired it for $100. Put it back in and 4 pulls later it started....Yippee!! I know it a little more expensive than if I could have bought it off the shelf but it was worth the investment to me.

Happy Boating all...c ya on the water!!
 
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